48 research outputs found

    Definition of a Solvent System for Spherical Crystallization of Salbutamol Sulfate by Quasi-Emulsion Solvent Diffusion (QESD) Method

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    International audienceIn this paper we describe how the spherical crystallization process by QESD method can be applied to a water-soluble drug, salbutamol sulfate. The type of solvent, antisolvent, and emulsiŸer and the concentration of emulsiŸer to be used for the production of spherical particles with a size range 80±500 mm are determined. Furthermore, the solvent/antisolvent ratio and the temperature difference between them (DT) are studied. It was observed that, in the case of salbutamol sulfate, the DT value has no in¯uence on the formation of spherical particles. A very large metastable zone of salbutamol sulfate in water could explain this phenomenon. Finally, the in¯uence of emulsiŸer concentration and of maturation time on the size of spherical particles is studied. The results show that these two parameters must be Ÿxed to control the size of the recovered particles

    Amorphous magnesium silicate ultrasound-assisted precipitation in a mixing system: Population balance modelling and crystallization rates identification

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    International audienceNatural talc is a very interesting filler for plastic and rubber materials and paints because it enables polymer matrix properties to be improved. Nano-sized particles are required to get a good dispersion of the solid in the polymer matrix. However, at the moment the main drawback in the use of natural talc is that, with a conventional milling process, nanometric particle sizes are difficult and expensive to obtain. A process of magnesium silicate synthesis made by ultrasound-assisted precipitation has been developed in two steps. The first step consists of the synthesis of amorphous magnesium silicate by precipitation from sodium metasilicate and acid magnesium chloride. In the second step, the amorphous solid is transformed in a crystalline solid under pressure. In this study an ultrasound-assisted synthesis of amorphous magnesium silicate is proposed. Some process parameters (ultrasound power, initial reactants molalities and reactants flow rate) have effects on the particle-size distribution. The population balance is modelled and solved by moments method in the steady state to identify nucleation and growth rates and agglomeration kernel as a function of operating conditions and to understand how these conditions affect the particle-size distribution

    Does intraoperative neuromonitoring of recurrent nerves have an impact on the postoperative palsy rate? Results of a prospective multicenter study

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    BACKGROUND: The impact of intraoperative neuromonitoring on recurrent laryngeal nerve palsy remains debated. Our aim was to evaluate the potential protective effect of intraoperative neuromonitoring on recurrent laryngeal nerve during total thyroidectomy. METHODS: This was a prospective, multicenter French national study. The use of intraoperative neuromonitoring was left at the surgeons\u27 choice. Postoperative laryngoscopy was performed systematically at day 1 to 2 after operation and at 6 months in case of postoperative recurrent laryngeal nerve palsy. Univariate and multivariate analyses and propensity score (sensitivity analysis) were performed to compare recurrent laryngeal nerve palsy rates between patients operated with or without intraoperative neuromonitoring. RESULTS: Among 1,328 patients included (females 79.9%, median age 51.2 years, median body mass index 25.6 kg/m), 807 (60.8%) underwent intraoperative neuromonitoring. Postoperative abnormal vocal cord mobility was diagnosed in 131 patients (9.92%), including 69 (8.6%) and 62 (12.1%) in the intraoperative neuromonitoring and nonintraoperative neuromonitoring groups, respectively. Intraoperative neuromonitoring was associated with a lesser rate of recurrent laryngeal nerve palsy in univariate analysis (odds ratio = 0.68, 95% confidence interval, 0.47; 0.98, P = .04) but not in multivariate analysis (oddsratio = 0.74, 95% confidence interval, 0.47; 1.17, P = .19), or when using a propensity score (odds ratio = 0.76, 95% confidence interval, 0.53; 1.07, P = .11). There was no difference in the rates of definitive recurrent laryngeal nerve palsy (0.8% and 1.3% in intraoperative neuromonitoring and non-intraoperative neuromonitoring groups respectively, P = .39). The sensitivity, specificity, and positive and negative predictive values of intraoperative neuromonitoring for detecting abnormal postoperative vocal cord mobility were 29%, 98%, 61%, and 94%, respectively. CONCLUSION: The use of intraoperative neuromonitoring does not decrease postoperative recurrent laryngeal nerve palsy rate. Due to its high specificity, however, intraoperative neuromonitoring is useful to predict normal vocal cord mobility. From the CHU de Nantes, Clinique de Chirurgie Digestive et Endocrinienne, Nantes, France; CHU Lille, UniversitĂ© de Lille, Chirurgie GĂ©nĂ©rale et Endocrinienne, Lille, France; CHU Nancy-HĂŽpital de Brabois, Service de Chirurgie Digestive, HĂ©pato-Biliaire, et Endocrinienne, Nancy, France; CHU Angers, Chirurgie Digestive et Endocrinienne, Angers, France; CHU de Toulouse-HĂŽpital Larrey, Chirurgie Thoracique, PĂŽle Voies Respiratoires, Toulouse; CHU Saint-Etienne-HĂŽpital Nord, ORL et Chirurgie Cervico-Faciale et Plastique, Saint-Etienne, France; CHU de Limoges-HĂŽpital Dupuytren, Chirurgie Digestive, GĂ©nĂ©rale et Endocrinienne, Limoges, France; CHU de Besançon-HĂŽpital Jean Minjoz, Chirurgie Digestive, Besançon, France; Centre Hospitalier du Mans, Service ORL et Chirurgie Cervico-Faciale, Le Mans, France; Centre Hospitalier Lyon-Sud, Chirurgie GĂ©nĂ©rale, Endocrinienne, Digestive et Thoracique, Pierre BĂ©nite, France; AP-HM-HĂŽpital de La Conception, Chirurgie GĂ©nĂ©rale, Marseille, France; CHU de Rennes-HĂŽpital Pontchaillou, Service ORL et Chirurgie Maxillo-Faciale, Rennes, France; CHU de Caen, ORL et Chirurgie Cervico-Faciale, Caen, France; CHU d\u27Angers, ORL et Chirurgie Cervico-Faciale, Angers, France; CHU de Nantes, Service ORL, Nantes, France; AP HP URCEco Ăźle-de-France, hĂŽpital de l\u27HĂŽtel-Dieu, Paris, France; DRCI, dĂ©partement Promotion, Nantes, France

    Naturalness and Fine Tuning in the NMSSM: Implications of Early LHC Results

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    We study the fine tuning in the parameter space of the semi-constrained NMSSM, where most soft Susy breaking parameters are universal at the GUT scale. We discuss the dependence of the fine tuning on the soft Susy breaking parameters M_1/2 and m0, and on the Higgs masses in NMSSM specific scenarios involving large singlet-doublet Higgs mixing or dominant Higgs-to-Higgs decays. Whereas these latter scenarios allow a priori for considerably less fine tuning than the constrained MSSM, the early LHC results rule out a large part of the parameter space of the semi-constrained NMSSM corresponding to low values of the fine tuning.Comment: 19 pages, 10 figures, bounds from Susy searches with ~1/fb include

    Sferična kristalizacija zdravilnih učinkovin

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    Spherical crystallization of drugs is the process of obtaining larger particles by agglomeration during crystallization. The most common techniques used to obtain such particles are spherical agglomeration and quasi-emulsion solvent diffusion. Ammonia diffusion systems and crystallo-co-agglomeration are extensions of these techniques. By controlling process parameters during crystallization, such as temperature, stirring rate, type and amount of solvents, or excipient selection, it is possible to control the formation of agglomerates and obtain spherical particles of the desired size, porosity, or hardness. Researchers have reported that the particles produced have improved micromeritic, physical, and mechanical properties, which make them suitable for direct compression. In some cases, when additional excipients are incorporated during spherical crystallization, biopharmaceutical parameters including the bioavailability of drugs can also be tailored.Sferična kristalizacija je postopek izdelave večjih delcev z aglomeracijo manjĆĄih med samo kristalizacijo. Najpogosteje uporabljeni tehniki za izdelavo takĆĄnih delcev sta sferična aglomeracija in kvaziemulzija z difuzijo topila. Sistem z difuzijo amoniaka in kristalo-ko-aglomeracija sta razĆĄiritvi teh dveh metod. Z nadzorovanjem procesnih parametrov med kristalizacijo, kot sta temperatura in hitrost meĆĄanja, z izbiro lastnosti in mnoĆŸine topil ter z izbiro pomoĆŸnih snovi, lahko vplivamo na nastanek aglomeratov in izdelamo sferične delce ĆŸelenih velikosti, primerne poroznosti ali trdote. Raziskovalci poročajo, da imajo izdelani delci izboljĆĄane pretočne lastnosti, izboljĆĄane druge fizikalne in mehanske lastnosti zaradi česar so primerni za direktno tabletiranje. V nekaterih primerih lahko ob vgradnji ustreznih pomoĆŸnih snovi, ki jih dodamo med procesom sferične kristalizacije, izboljĆĄamo tudi biofarmacevtske lastnosti zdravilnih učinkovin vključno s povečanjem bioloĆĄke uporabnosti

    Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

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    PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

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    PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Particle design Part A: Nucleation kinetics of ketoprofen

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    International audienceThis work is part of a study of the spherical crystallization process by the quasi-emulsion method. The induction time of ketoprofen in acetone + ketoprofen solutions and in solutions of acetone + water + ketoprofen have been experimentally determined. Ketoprofen presents a large metastable zone in the case of primary nucleation and a very narrow metastable zone in the case of secondary nucleation. The rate of primary nucleation in pure acetone has been measured and is correlated by the equation 1.0 × 1036 exp (-2.68 × 106/T3 × ln2S) (in number m3 s−1). The physico-chemical properties—phase diagram of the system acetone + water + ketoprofen involved in the process-are given. An experiment to study crystallization into a droplet is presented

    Particle design Part B: batch quasi-emulsion process and mechanism of grain formation of ketoprofen

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    International audienceThis study deals with the spherical crystallization process by the quasi-emulsion mechanism, applied to a pharmaceutical. The objective is to produce spherical agglomerates made of a number of small crystals of the drug, having properties adequate for direct compression when manufacturing tablets. The aim of this work is to make the link between the process and these properties. The different steps occurring in the process are the fortnation of an emulsion whose droplets are made of the drug dissolved in a solvent, the creation of the supersaturation of the drug in the droplets by mass and heat transfer and the nucleation, growth and agglomeration of drug crystals inside the droplets. The process has been carried out in a batch laboratory scale device. The variation of the operating parameters on the one hand and of the relative proportions of the various components on the other have enabled us to determine the influence on the internal and external structures of the produced agglomerates which influence the ability to be compressed. The identitication of the phenomena occurring has led to a proposed mechanism for the formation of the agglomerates
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